这表示 explain 是用于解释查询的。

This tells us that the explain was used to explain the query. Snippet of the plan

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示例连接器：解释查询。

Example connector: Interpreting queries.

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与ItemFinder不同，Query还需要一些相当简单的解析，以便正确地解释查询表达式。

Query, unlike ItemFinder, also requires some relatively simple parsing to interpret query expressions correctly.

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